Spatio-temporal distribution of aerobacterias in the palangana's landfill, Santa Marta (Colombia)

Abstract

Different stages during the degradation of municipal solid wastes (MSW) in landfills can contribute to the  emission of bioaerosols, which may represent a health hazard causing allergic, respiratory and infectious  diseases. However, the studies related to the generation of airborne bacteria in landfill sites in Colombia are  still scarce. Therefore, this study was aimed to establish the spatial and temporal distribution of airborne  bacteria generated during the final disposal of MSW at the Palangana landfill site, located at Sant a Marta district. To achieve this aim, three monitoring locations were selected at different operations taking place in  the landfill site, and following the wind direction; these locations corresponded to the active cell, the close cell  and the leachate collection pond, where six monitoring campaigns were performed both in the morning and  afternoon. Airborne bacteria were collected on standard plate count agar using a two-stage cascade impactormodel 10-800 (Tisch Environmental, Inc.), operating at 28,3 l/min during 3 min (sampling time) and located  at 1,5 m height. Plates were incubated for 48 h at 28°C for colony counting. The highest airborne bacteria  concentration in the morning sampling was obtained at the leachate pond (2.320 CFU/m3), whereas in  afternoon samplings the highest concentration as obtained in the active cell (3.545 CFU/m3). Besides, there   was higher concentration of breathable bacteria compared to the sedimentable bacteria, confirming the health  hazard for site workers due to the exposure to the airborne bacteria that can reach the respiratory system.